Are tropical diseases gaining ground in Europe?

The Asian tiger mosquito is regarded in Europe as the most important vector for dengue, West Nile, and Chikungunya viruses. Originally located in Southeast Asia, it is possible that the mosquito could have already spread to large parts of southern Europe and even overwintered in southern Germany. According to the prognosis of the European Center for Disease Control and Prevention (ECDC), by 2030 it could even reach southern Sweden.

Chikungunya

The name Chikungunya is Swahili for "the curved walking", which also figuratively describes the disease, characterized by severe joint and limb pain as its main symptoms. Other symptoms include intense fever attacks and flu-like symptoms, which are relatively harmless and usually disappear after just a few days. However in children and those with a weakened immune system, as well as in older people, the disease can be severe and disabling. Although Chikungunya occurs mainly in tropical and subtropical areas, isolated cases have been reported in Europe, such as in France and Madeira, including an outbreak of more than 200 patients in Italy.
 

Dengue fever

The World Health Organization (WHO) estimates that approximately 390 million people get infected with the Dengue virus every year. Dengue fever is characterized by fever, as well as headaches and joint pains, which occur about 3 to 7 days after infection and only last briefly. In general, the infection is subclinical or completely asymptomatic. In rare cases, the course of the disease can be more severe. Although the risk of infection in Europe is minimal, the main risk area is Madeira, which had seen an outbreak of more than 1000 people between 2012 and 2013. In addition, isolated autochthonous cases have occurred in France and Croatia over the past few years.
 

West Nile fever

This particular infection usually remains undetected. Only about 20% of the patients suffer from flu-like symptoms. But in very rare cases, patients may potentially develop fatal encephalitis or meningitis additionally. So far, no cases of transmission of the fever have been reported in Europe in 2017, while in 2016 southern Europe, Hungary and the metropolitan region of Vienna reported several hundred cases.
 

Malaria

In recent years, the fight against tropical diseases has been quite successful. In 2016, the WHO announced that malaria had been eliminated in Europe. The number of autochthonous infections decreased from over 90,000 cases in 1995 to zero in 2015.
 

Leishmaniasis

Leishmaniasis is caused by the protozoa Leishmania, and is transmitted by the bite of infected female sandflies. Although the disease is classified as a tropical disease, it also occurs endemically in some southern European countries. Most cases commonly present as the more harmless cutaneous leishmaniasis, but the more dangerous visceral form can also occur in isolated European countries. Currently the risk of infection with these diseases in Europe is relatively low. Travelling to tropical and subtropical areas poses as the biggest risk for getting infected with the diseases. It is quite likely that the topic will gain more relevance in Europe in the near future as well.
 

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